New regulatory rules focus on correlation between signals transmitted from different antennas of a wireless communication device that can lead to array gain (intentional or unintentional), which increases the directional gain of the wireless communication device and leads to higher radiation levels in some directions. This contribution of antenna array gain to the directional gain of the transmitter is considered in all measurement situations where conducted measurements are combined with directional antenna gain to determine compliance with in-band regulatory limits. Signals can be correlated anytime the same signal (or space-time stream) is transmitted across two or more antennas in a given symbol period even with different phase shifts and time delays.